Noise. Noise refers to unwanted levels of sound, mechanical energy transmitted by
pressure waves in a compressible medium such as air that make up what we hear.
Noise contour. Noise contours consist of noise impact lines constructed by connecting
points of equal noise level measured in dB and identifying areas on a map that fall within
that particular dB noise contour.
Noise‐sensitive receptors / noise‐sensitive land uses. Noise‐sensitive receptors are
locations and uses typically more sensitive to noise impacts, including residential areas,
hospitals, convalescent homes and facilities, schools, libraries, churches, recreational
areas, and other similar land uses.
Noise zones. The Army uses a series of noise zones to identify noise levels associated
with military operations and what types of land uses are either compatible or not
recommended within the specific zones. Army Regulation (AR) 200‐1 lists housing,
schools, and medical facilities as examples of noise sensitive land uses, which are
identified as land uses that are generally acceptable within the Noise Zone I, normally not
recommended in Noise Zone II, and not recommended in Noise Zone III. The Army and
AZARNG utilize three noise zones, described as follows.
Noise Zone I includes all areas in which the PK15(met) decibels are less than 87
(for small arms), the A weighted average day night level (ADNL) is less than 65
(for aircraft), and / or the C‐weighted average day night level (CDNL) is less than
62 (for large arms and explosions). This zone is the furthest zone away from the
noise source and is generally suitable for all types of land use.
Noise Zone II includes areas where the PK15(met) decibels are between 87 and
104, the ADNL is between 65 and 75, and/or the CDNL is between 62 and 70.
Although local conditions such as availability of developable land or cost may
result in development of noise‐sensitive land uses in Zone II, this type of land use
is strongly discouraged on the installation and in surrounding communities. All
viable alternatives should be considered to limit development in Zone II to
non‐sensitive activities such as industry, manufacturing, transportation,
agriculture, and resource protection.
Noise Zone III includes areas closest to the source of noise. It includes
PK15(met) decibels greater than 104, ADNL greater than 75, and/or CDNL
greater than 70. No noise sensitive uses should occur within this area due to the
severity of noise.
There is also a Land Use Planning Zone (LUPZ) at the outer end of Noise Zone I
that includes areas where the CDNL is between 57 and 62 or the ADNL is
between 60 and 65. It does not include land for PK15(met). This zone accounts
Background Report
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